Red Hat ENTERPRISE LINUX 4 System Administration Manual page 171

Establishing an Ethernet Connection
Figure 17.3. Ethernet Device
Be sure to select File => Save to save the changes.
After adding the Ethernet device, you can edit its configuration by selecting the device from the device
list and clicking Edit. For example, when the device is added, it is configured to start at boot time by
default. To change this setting, select to edit the device, modify the Activate device when computer
starts value, and save the changes.
When the device is added, it is not activated immediately, as seen by its Inactive status. To activate
the device, select it from the device list, and click the Activate button. If the system is configured to
activate the device when the computer starts (the default), this step does not have to be performed
again.
If you associate more than one device with an Ethernet card, the subsequent devices are device
aliases. A device alias allows you to setup multiple virtual devices for one physical device, thus giving
the one physical device more than one IP address. For example, you can configure an eth1 device
Section 17.11, "Device Aliases".
and an eth1:1 device. For details, refer to
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